Valve



May 31, 1949. K. MacDONALD 2,471,880

VALVE Filed Nov. 2, 1945 KARL MACDWMD INVENTOR.

Patented May 3.1, 1949 2,471,880

VALVE V l "'KarL'MacDonald, WellsvillepN, Y., assignor' to WorthingtonPump and Machinery Cor-para? 'tion, Harrison, N. J., a corporationofDelaware wkpplioation November 2, 1945, SerialNo; 626,256

, 31Claims, (01. 251-167) '1 This invention relates to valves, and moreparticularly to valve seats employed in hand operated nozzle controlvalves ,used on steam turbines to regulate the effective nozzle areaupright wall tend-a fiatz bqttom suriacelliupozg which the valve seatrests.

As pointed out hereinbefore, considerable difficulty has beenexperienced in providing a lasting of a steam turbine. 5 fluid-tightseal about the valve seat 5 due to In valves of this type, the valve andvalve the conditions encountered in the use of the valve seat aresubject to great stresses, due to the fact structure.

that high pressure steam in the steam ring of Therefore, a novelconstruction of valve seat a turbine contacts one side of the valveseat, has been provided which, as clearly shown in while low pressuresteam contacts the other side Figures 1 and 2 ofthe drawings, is in theform of when the valve is seated. The valve seats are made of a metaldiffering in expansion and con traction qualities than the metal used ina steam ring of a turbine, and it has been found in praca ring having aseat 8 against which the valve 9 rests when in closed position. Thevalve seat 5 has a plurality of radially extending annular ribs ll)formed thereon spaced from each other by ,tice that when the valve seatis screwed into the annular spaces II. ,The annular ribs I0 inclinesteam ring it leaks, due to unequal expansion at acute angles from theplane of the flat surface and contraction of the parts under temperatureof the valve seat 5 which rests upon the bottom variances, and if thevalve seats are shrunk into surface 1 of the opening 2, and the portionof the steam ring they become loose and conthe valve seat 5 below thelowermost annular sequently leak. space H and adjacent to the under fiatsurface of It is an object of the present invention to prothe valve seatis of slightly less diameter than the vide a novel form of valve seatwhich will be diameter of the ribs III, as clearly shown at H tightlyheld in non-leaking position under all in Figure 1 of the drawings.conditions met with in its use. When assembling the valve structure, thevalve With these and other objects in view, as may seat is cooled orchilled such as by Dry Ice or appear from the accompanyingspecification, the a deep freeze method to cause contraction thereofinvention consists of various features of conso that it may be slippedinto the counterbore struction and combination of parts, which willformed in the housing ll. After the valve seat be first described inconnection with the achas been slipped into the counterbore of theopencompanying drawings, showing a valve of a ing 2, it will, underatmospheric temperature, preferred form embodying the invention, andexpand as it heats up from its previously chilled the features formingthe invention will be specifcondition, and it will form a fluidtight,firm enically pointed out in the claims. gagement between the perimeterof the ribs [0 In the drawings: and the annular wall 6. The annular ribsor fins Figure 1 is a longitudinal section through a ID will flexslightly when the valve seat 5 expands nozzle control valve of a steamturbine showing under the temperature variances encountered the improvedvalve seat. during the use of the valve, and therefore will Figure 2 isa perspective view of the improved not crush or become loosened in thecountervalve seat. bore of the opening 2.

Referring more particularly to the drawings, It will be noted that theribs I0 incline outthe valve housing, which in the present inventionwardly towards the high pressure steam ring 3, is a P r f the Casinghousing of a Steam that is, they incline outwardly towards the pointturbine, is indicated at I, and it is provided with where the greatestpressure is exerted against a port 2 which establishes communicationbethem so that as the housing I and the valve seat tween the steam ring3-which contains high presare heated by the high pressure steam in thesure steam and the distribution space 4 which steam ring3 and expand,the pressure against the when the port 2 is closed contains low pressureribs Ill will tend to force them downwardly or steam or substantially avacuum. The opening away from the point of high pressure contact, 2 iscounterbored to form a seat for the valve causing them always tomaintain firm, fluid-tight seat 5, such counterbore including an annularengagement with the annular wall 6.

It will be understood that the invention is not to be limited to thespecific construction. or arrangement of parts shown, but that they maybe widely modified within the invention defined by the claims.

What is claimed is:

1. In combination, a valve body provided with a valve seat receivingcounterbore having an annular valve seat engaging wall and a bottomsurface for engagement with a valve seat, a valve seat resting on saidbottom surface, said valve seat having a plurality of spaced annularribs formed upon its perimeter and having perimetrical engagement withsaid annular wall, said annular ribs inclining at acute angles to saidannular wall and to the face of said seat which engages said bottomsurface.

2. In a nozzle control valve for steam turbines: the combination with avalve housing containing a high pressure, high temperature steam ringand a low pressure distribution space; said housing provided with anopening establishing communication between said high pressure, hightemperature steam ring and said low pressure distribution space; saidopening provided with a valve seat receiving counterbore having anannular 'wall and a fiat bottom surface; a valve seat seated on saidfiat surface; a plurality of annular ribs formed about the perimeter ofsaid valve seat and having perimetrical contact with the annular wall ofsaid counterbore; said annular ribs being inclined towards said highpressure, high temperature steam ring as they extend outwardly from theperimeter of the valve seat.

3. A nozzle control valve for steam turbines as claimed in claim 2wherein the portion of said valve seat adjacent to the bottom surface ofsaid counterbore is of smaller diameter than the diameter of the spacedribs and is free from engagement with the annular wall of thecounterbore.

KARL MAcDONALD.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,512,496 Snead Oct. 21, 19241,891,460 Vlahek Dec. 20, 1932 2,174,337 Welsmiller Sept. 26, 1939

